There are growing concerns in energy markets about supplies from the world's 13th largest producer but Shell won't say how much oil is not being exported. The government says oil thefts averaged 300,000 barrels a day and cost $12 billion last year.

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Shell closed the terminal March 4 to repair a leak on an undersea pipeline. Niger Delta militants claimed the sabotage and said March 27 that scuba divers had further damaged repair work.